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This article describes a study of active tectonics, earthquake deformation, active uplift, scarp morphology and seismic geohazards microzonation in the Hazara-Kashmir Syntaxis, an active antiformal synclinal structure in the northern Himalayas of Pakistan. It notes that the active faults along the structure show the evidence for deformation, deflected or offset streams, nick points, uplifted and tilted terraces and seismicity.

Radon concentrations were measured in kucha, semikucha and pucka houses located on the sedimentary rocks of Early Pleistocene-Pliocene Soan Formation, Pleistocene Mirpur conglomerate and recent deposits. The radon concentration was measured using CN 85 nuclear tracks etch detectors in box type dosimeters installed in the bedrooms and kitchens of the houses. It was found to vary from 14±7Bqm-3 to 258±28Bqm-3 with an average of 105±17Bqm-3. The average radon concentration in the kucha, semi-kucha and pucka houses was 78±15Bqm-3, 108±18Bqm-3 and 108± 18Bqm-3 respectively. The increase in radon concentration from kucha to pucka houses was attributed to the type of house, differing humidity related to the Mangla Dam, temperature, bed rock geology, structures (joints, fractures and faults), aggregates and uraniumbearing sand. This study shows that the average radon level is within the accepted safe health limit (200Bqm-3) for the inhabitants of New Mirpur Azad Kashmir, Pakistan. [ABSTRACT FROM AUTHOR]

This study reported the detrital zircon U-Pb geochronology of the Cenozoic sequence exposed in Kotli, northwestern Himalaya, Pakistan, which forms part of the Kashmir foreland basin. The U-Pb detrital age patterns of the Paleocene Patala Formation show a major age cluster between ~130–290 Ma, ~500–1000 Ma and ~1000–1500 Ma, which mainly resembles the lesser and higher Himalayan sequence. However, the younger age pattern (~130–290 Ma) can be matched to the ages of the ophiolites exposed along the Indus–Tsangpo suture zone. In addition, two younger grains with 57 Ma and 55 Ma ages may indicate a contribution from the Kohistan-Ladakh arc. The detrital zircons in the upper Tertiary sequence show the increased input of younger detrital ages <100 Ma, with more pronounced peaks at ~36–58 Ma, ~72–94 Ma and ~102–166 Ma, indicating the strong resemblance to the Asian sources including the Kohistan–Ladakh arc, Karakoram block and Gangdese batholith. This provenance shift, recorded in the upper portion of Patala Formation and becoming more visible in the upper Tertiary clastic sequence (Kuldana and Murree formations), is related to the collision of the Indian and Asian plates in the northwestern Himalayas. Considering the age of the Patala Formation, we suggest that the Indian and Asian plates collided during 57–55 Ma in the northwestern Himalayas, Pakistan. [ABSTRACT FROM AUTHOR]

This article describes gravity and geological studies of the Hazara-Kashmir Syntaxis in Pakistan. It notes that continued northward migration of the Indian plate in the area has been overridden by slices of its own northern margin, resulting in slight thickening of the crust. Researcher observed two types of deformation, one is in the crystalline crust and the other in both the sedimentary wedge and crystalline crust.

This article focuses on a thin skin tectonic study based on gravity conducted along the western limb of the Hazara Kashmir Syntaxis in Muzaffarabad and adjoining areas in Sub Himalayas in Azad Kashmir, Pakistan. It notes that gravity study based on geological and gravity data depicts the thickness of crust and thin skin faults of the area. The findings of the study are explored.

Abstract: Distribution of the mass movements triggered by the 2005 Kashmir earthquake was analysed in the vicinity of Jhelum Valley, Neelum Valley, and Muzaffarabad in the Northeast Himalayas of Pakistan. Mass movements were mapped using SPOT satellite imagery and field investigations. Geographic information systems (GIS) were used to analyse the relations of the distribution of these mass movements using various parameters, such as distance from an earthquake source (epicentre and fault), topographic parameters (slope steepness, slope aspect, and elevation) and geological units. The results of the analysis indicate that the mass movement concentration decreases with increased distance from the earthquake epicentre and the reactivated Muzaffarabad Fault. The maximum concentration of mass movements is near the epicentre and a fault. A significant occurrence and concentration of mass movements were evident at slope angles between 31–40°. The preferred orientations of the mass movements were in southerly directions. The concentrations of mass movements differ substantially among various geological units. Mass movements are widely distributed in the Miocene Murree Formation, whereas the concentration of mass movements is higher in the Cambrian Muzaffarabad Formation. The median mass movement concentration inflicted by the epicentre and the Muzaffarabad Fault exhibited no significant differences (KS =0.505; p =0.961). The results of the PCA reveal that the largest variance in mass movement concentration is attributed to the distance from the epicentre and the Muzaffarabad Fault. The findings suggest that the mass movement concentration is primarily dependent on the distance from the earthquake source. In addition, the topographic parameters and geological units played subordinate roles in the distribution of mass movements. [Copyright &y& Elsevier]